Method and apparatus of establishing access channel in wireless communication systems

ABSTRACT

A method and apparatus for establishing an access channel in a wireless communication system is provided, comprising receiving an AccessGrant on a carrier on which the last probe was transmitted and ending an access probe transmission upon receiving the AccessGrant. A method and apparatus is further provided, comprising determining expiration of an access grant timer and ending an access probe transmission upon the expiration of the timer. A method and apparatus is further provided comprising receiving an IdleState.IdleHO indication and ending an access probe transmission upon receiving the IdleState.IdleHO indication. A method and apparatus is further provided receiving a new AttemptAccess command, wherein the AttemptAccess command is processed after a current probe transmission ends and ending an access probe transmission on receiving the new AttemptAccess command.

CLAIM OF PRIORITY UNDER 35 U.S.C. § 119

The present Application for patent claims priority to ProvisionalApplication Ser. No. 60/731,037, entitled “METHOD AND APPARATUS FORPROVIDING MOBILE BROADBAND WIRELESS HIGHER MAC”, filed Oct. 27, 2005,assigned to the assignee hereof, and expressly incorporated herein byreference.

BACKGROUND

1. Field

The present disclosure relates generally to wireless communication andmore particularly to method and apparatus for establishing an accesschannel.

2. Background

Wireless communication systems have become a prevalent means by which amajority of people worldwide have come to communicate. Wirelesscommunication devices have become smaller and more powerful in order tomeet consumer needs and to improve portability and convenience. Theincrease in processing power in mobile devices such as cellulartelephones has lead to an increase in demands on wireless networktransmission systems. Such systems typically are not as easily updatedas the cellular devices that communicate there over. As mobile devicecapabilities expand, it can be difficult to maintain an older wirelessnetwork system in a manner that facilitates fully exploiting new andimproved wireless device capabilities.

Wireless communication systems generally utilize different approaches togenerate transmission resources in the form of channels. These systemsmay be code division multiplexing (CDM) systems, frequency divisionmultiplexing (FDM) systems, and time division multiplexing (TDM)systems. One commonly utilized variant of FDM is orthogonal frequencydivision multiplexing (OFDM) that effectively partitions the overallsystem bandwidth into multiple orthogonal subcarriers. These subcarriersmay also be referred to as tones, bins, and frequency channels. Eachsubcarrier can be modulated with data. With time division basedtechniques, a each subcarrier can comprise a portion of sequential timeslices or time slots. Each user may be provided with a one or more timeslot and subcarrier combinations for transmitting and receivinginformation in a defined burst period or frame. The hopping schemes maygenerally be a symbol rate hopping scheme or a block hopping scheme.

Code division based techniques typically transmit data over a number offrequencies available at any time in a range. In general, data isdigitized and spread over available bandwidth, wherein multiple userscan be overlaid on the channel and respective users can be assigned aunique sequence code. Users can transmit in the same wide-band chunk ofspectrum, wherein each user's signal is spread over the entire bandwidthby its respective unique spreading code. This technique can provide forsharing, wherein one or more users can concurrently transmit andreceive. Such sharing can be achieved through spread spectrum digitalmodulation, wherein a user's stream of bits is encoded and spread acrossa very wide channel in a pseudo-random fashion. The receiver is designedto recognize the associated unique sequence code and undo therandomization in order to collect the bits for a particular user in acoherent manner.

A typical wireless communication network (e.g., employing frequency,time, and/or code division techniques) includes one or more basestations that provide a coverage area and one or more mobile (e.g.,wireless) terminals that can transmit and receive data within thecoverage area. A typical base station can simultaneously transmitmultiple data streams for broadcast, multicast, and/or unicast services,wherein a data stream is a stream of data that can be of independentreception interest to a mobile terminal. A mobile terminal within thecoverage area of that base station can be interested in receiving one,more than one or all the data streams transmitted from the base station.Likewise, a mobile terminal can transmit data to the base station oranother mobile terminal. In these systems the bandwidth and other systemresources are assigned utilizing a scheduler.

SUMMARY

The following presents a simplified summary of one or more aspects inorder to provide a basic understanding of such aspects. This summary isnot an extensive overview of all contemplated aspects, and is intendedto neither identify key or critical elements of all aspects nordelineate the scope of any or all aspects. Its sole purpose is topresent some concepts of one or more aspects in a simplified form as aprelude to the more detailed description that is presented later.

The signals signal formats, signal exchanges, methods, processes, andtechniques disclosed herein provide several advantages over knownapproaches. These include, for example, reduced signaling overhead,improved system throughput, increased signaling flexibility, reducedinformation processing, reduced transmission bandwidth, reduced bitprocessing, increased robustness, improved efficiency, and reducedtransmission power.

According to an embodiment, a method is provided for establishing anaccess channel. One embodiment comprises receiving an access grant onthe carrier on which the last probe was transmitted and ending accessprobe transmission upon receiving the AccessGrant. Another embodimentcomprises determining expiration of an access grant timer and endingaccess probe transmission upon the expiration of the timer. Anotherembodiment comprises receiving an IdleState.IdleHO indication and endingaccess probe transmission upon receiving the IdleState.IdleHOindication. Yet another embodiment comprises receiving a newAttemptAccess command, wherein the AttemptAccess command is processedafter the current probe transmission ends and ending access probetransmission on receiving the new AttemptAccess command.

According to another embodiment, a computer-readable medium is describedhaving a first set of instructions for receiving an access grant on thecarrier on which the last probe was transmitted and a second set ofinstructions for ending access probe transmission upon receiving theAccessGrant. Another aspect of computer-readable medium comprises afirst set of instructions for determining expiration of an access granttimer and a second set of instructions for ending access probetransmission upon the expiration of the timer. Another aspect of themedium comprises a first set of instructions for receiving anIdleState.IdleHO indication and a second set of instructions for endingaccess probe transmission upon receiving the IdleState.IdleHOindication. Yet another aspect of the medium comprises a first set ofinstructions for receiving a new AttemptAccess command, wherein theAttemptAccess command is processed after the current probe transmissionends and a firsts et of instructions for ending access probetransmission on receiving the new AttemptAccess command.

According to yet another embodiment, an apparatus operable in a wirelesscommunication system is described which includes means for receiving anaccess grant on the carrier on which the last probe was transmitted anda means for ending access probe transmission upon receiving theAccessGrant. Another aspect of the apparatus comprises a means fordetermining expiration of an access grant timer and a means for endingaccess probe transmission upon the expiration of the timer. Anotheraspect of the apparatus comprises a means for receiving anIdleState.IdleHO indication and a means for ending access probetransmission upon receiving the IdleState.IdleHO indication. Yet anotheraspect of the apparatus comprises means for receiving a newAttemptAccess command, wherein the AttemptAccess command is processedafter the current probe transmission ends and a means for ending accessprobe transmission on receiving the new AttemptAccess command

To the accomplishment of the foregoing and related ends, the one or moreaspects comprise the features hereinafter fully described andparticularly pointed out in the claims. The following description andthe annexed drawings set forth in detail certain illustrative aspects ofthe one or more aspects. These aspects are indicative, however, of but afew of the various ways in which the principles of various aspects maybe employed and the described aspects are intended to include all suchaspects and their equivalents.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates aspects of a multiple access wireless communicationsystem.

FIG. 2 illustrates aspects of a transmitter and receiver in a multipleaccess wireless communication system.

FIGS. 3A and 3B illustrate aspects of superframe structures for amultiple access wireless communication system.

FIG. 4 illustrates communication between an access terminal and anaccess network.

FIG. 5A illustrates a flow diagram of a process by access terminal.

FIG. 5B illustrates a module for establishing an access channel by anaccess terminal.

DETAILED DESCRIPTION

Various aspects are now described with reference to the drawings,wherein like reference numerals are used to refer to like elementsthroughout. In the following description, for purposes of explanation,numerous specific details are set forth in order to provide a thoroughunderstanding of one or more aspects. It may be evident, however, thatsuch aspect(s) may be practiced without these specific details. In otherinstances, well-known structures and devices are shown in block diagramform in order to facilitate describing one or more aspects.

Referring to FIG. 1, a multiple access wireless communication systemaccording to one aspect is illustrated. A multiple access wirelesscommunication system 100 includes multiple cells, e.g. cells 102, 104,and 106. In the aspect of FIG. 1, each cell 102, 104, and 106 mayinclude an access point 150 that includes multiple sectors. The multiplesectors are formed by groups of antennas each responsible forcommunication with access terminals in a portion of the cell. In cell102, antenna groups 112, 114, and 116 each correspond to a differentsector. In cell 104, antenna groups 118, 120, and 122 each correspond toa different sector. In cell 106, antenna groups 124, 126, and 128 eachcorrespond to a different sector.

Each cell includes several access terminals which are in communicationwith one or more sectors of each access point. For example, accessterminals 130 and 132 are in communication base 142, access terminals134 and 136 are in communication with access point 144, and accessterminals 138 and 140 are in communication with access point 146.

Controller 130 is coupled to each of the cells 102, 104, and 106.Controller 130 may contain one or more connections to multiple networks,e.g. the Internet, other packet based networks, or circuit switchedvoice networks that provide information to, and from, the accessterminals in communication with the cells of the multiple accesswireless communication system 100. The controller 130 includes, or iscoupled with, a scheduler that schedules transmission from and to accessterminals. In other aspects, the scheduler may reside in each individualcell, each sector of a cell, or a combination thereof.

As used herein, an access point may be a fixed station used forcommunicating with the terminals and may also be referred to as, andinclude some or all the functionality of, a base station, a Node B, orsome other terminology. An access terminal may also be referred to as,and include some or all the functionality of, a user equipment (UE), awireless communication device, terminal, a mobile station or some otherterminology.

It should be noted that while FIG. 1, depicts physical sectors, i.e.having different antenna groups for different sectors, other approachesmay be utilized. For example, utilizing multiple fixed “beams” that eachcover different areas of the cell in frequency space may be utilized inlieu of, or in combination with physical sectors. Such an approach isdepicted and disclosed in copending U.S. patent application Ser. No.11/260,895, entitled “Adaptive Sectorization In Cellular System.”

Referring to FIG. 2, a block diagram of an aspect of a transmittersystem 210 and a receiver system 250 in a MIMO system 200 isillustrated. At transmitter system 210, traffic data for a number ofdata streams is provided from a data source 212 to transmit (TX) dataprocessor 214. In an aspect, each data stream is transmitted over arespective transmit antenna. TX data processor 214 formats, codes, andinterleaves the traffic data for each data stream based on a particularcoding scheme selected for that data stream to provide coded data.

The coded data for each data stream may be multiplexed with pilot datausing OFDM, or other orthogonalization or non-orthogonalizationtechniques. The pilot data is typically a known data pattern that isprocessed in a known manner and may be used at the receiver system toestimate the channel response. The multiplexed pilot and coded data foreach data stream is then modulated (i.e., symbol mapped) based on one ormore particular modulation schemes (e.g., BPSK, QSPK, M-PSK, or M-QAM)selected for that data stream to provide modulation symbols. The datarate, coding, and modulation for each data stream may be determined byinstructions performed on provided by processor 230.

The modulation symbols for all data streams are then provided to a TXprocessor 220, which may further process the modulation symbols (e.g.,for OFDM). TX processor 220 then provides N_(T) modulation symbolstreams to N_(T) transmitters (TMTR) 222 a through 222 t. Eachtransmitter 222 receives and processes a respective symbol stream toprovide one or more analog signals, and further conditions (e.g.,amplifies, filters, and upconverts) the analog signals to provide amodulated signal suitable for transmission over the MIMO channel. N_(T)modulated signals from transmitters 222 a through 222 t are thentransmitted from N_(T) antennas 224 a through 224 t, respectively.

At receiver system 250, the transmitted modulated signals are receivedby NR antennas 252 a through 252 r and the received signal from eachantenna 252 is provided to a respective receiver (RCVR) 254. Eachreceiver 254 conditions (e.g., filters, amplifies, and downconverts) arespective received signal, digitizes the conditioned signal to providesamples, and further processes the samples to provide a corresponding“received” symbol stream.

An RX data processor 260 then receives and processes the NR receivedsymbol streams from NR receivers 254 based on a particular receiverprocessing technique to provide N_(T) “detected” symbol streams. Theprocessing by RX data processor 260 is described in further detailbelow. Each detected symbol stream includes symbols that are estimatesof the modulation symbols transmitted for the corresponding data stream.RX data processor 260 then demodulates, deinterleaves, and decodes eachdetected symbol stream to recover the traffic data for the data stream.The processing by RX data processor 218 is complementary to thatperformed by TX processor 220 and TX data processor 214 at transmittersystem 210.

RX data processor 260 may be limited in the number of subcarriers thatit may simultaneously demodulate, e.g. 512 subcarriers or 5 MHz, andsuch a receiver should be scheduled on a single carrier. This limitationmay be a function of its FFT range, e.g. sample rates at which theprocessor 260 may operate, the memory available for FFT, or otherfunctions available for demodulation. Further, the greater the number ofsubcarriers utilized, the greater the expense of the access terminal.

The channel response estimate generated by RX processor 260 may be usedto perform space, space/time processing at the receiver, adjust powerlevels, change modulation rates or schemes, or other actions. RXprocessor 260 may further estimate the signal-to-noise-and-interferenceratios (SNRS) of the detected symbol streams, and possibly other channelcharacteristics, and provides these quantities to a processor 270. RXdata processor 260 or processor 270 may further derive an estimate ofthe “operating” SNR for the system. Processor 270 then provides channelstate information (CSI), which may comprise various types of informationregarding the communication link and/or the received data stream. Forexample, the CSI may comprise only the operating SNR. In other aspects,the CSI may comprise a channel quality indicator (CQI), which may be anumerical value indicative of one or more channel conditions. The CSI isthen processed by a TX data processor 278, modulated by a modulator 280,conditioned by transmitters 254 a through 254 r, and transmitted back totransmitter system 210.

At transmitter system 210, the modulated signals from receiver system250 are received by antennas 224, conditioned by receivers 222,demodulated by a demodulator 240, and processed by a RX data processor242 to recover the CSI reported by the receiver system. The reported CSIis then provided to processor 230 and used to (1) determine the datarates and coding and modulation schemes to be used for the data streamsand (2) generate various controls for TX data processor 214 and TXprocessor 220. Alternatively, the CSI may be utilized by processor 270to determine modulation schemes and/or coding rates for transmission,along with other information. This may then be provided to thetransmitter which uses this information, which may be quantized, toprovide later transmissions to the receiver.

Processors 230 and 270 direct the operation at the transmitter andreceiver systems, respectively. Memories 232 and 272 provide storage forprogram codes and data used by processors 230 and 270, respectively.

At the receiver, various processing techniques may be used to processthe NR received signals to detect the N_(T) transmitted symbol streams.These receiver processing techniques may be grouped into two primarycategories (i) spatial and space-time receiver processing techniques(which are also referred to as equalization techniques); and (ii)“successive nulling/equalization and interference cancellation” receiverprocessing technique (which is also referred to as “successiveinterference cancellation” or “successive cancellation” receiverprocessing technique).

While FIG. 2 discusses a MIMO system, the same system may be applied toa multi-input single-output system where multiple transmit antennas,e.g. those on a base station, transmit one or more symbol streams to asingle antenna device, e.g. a mobile station. Also, a single output tosingle input antenna system may be utilized in the same manner asdescribed with respect to FIG. 2.

The transmission techniques described herein may be implemented byvarious means. For example, these techniques may be implemented inhardware, firmware, software, or a combination thereof. For a hardwareimplementation, the processing units at a transmitter may be implementedwithin one or more application specific integrated circuits (ASICs),digital signal processors (DSPs), digital signal processing devices(DSPDs), programmable logic devices (PLDs), field programmable gatearrays (FPGAs), processors, controllers, micro-controllers,microprocessors, processors, other electronic units designed to performthe functions described herein, or a combination thereof. The processingunits at a receiver may also be implemented within one or more ASICs,DSPs, processors, and so on.

For a software implementation, the transmission techniques may beimplemented with modules (e.g., procedures, functions, and so on) thatperform the functions described herein. The software codes may be storedin a memory (e.g., memory 230, 272 x or 272 y in FIG. 2) and executed bya processor (e.g., processor 232, 270 x or 270 y). The memory may beimplemented within the processor or external to the processor.

It should be noted that the concept of channels herein refers toinformation or transmission types that may be transmitted by the accesspoint or access terminal. It does not require or utilize fixed orpredetermined blocks of subcarriers, time periods, or other resourcesdedicated to such transmissions.

Referring to FIGS. 3A and 3B, aspects of superframe structures for amultiple access wireless communication system are illustrated. FIG. 3Aillustrates aspects of superframe structures for a frequency divisionduplexed (FDD) multiple access wireless communication system, while FIG.3B illustrates aspects of superframe structures for a time divisionduplexed (TDD) multiple access wireless communication system. Thesuperframe preamble may be transmitted separately for each carrier ormay span all of the carriers of the sector.

In both FIGS. 3A and 3B, the forward link transmission is divided intounits of superframes. A superframe may consist of a superframe preamblefollowed by a series of frames. In an FDD system, the reverse link andthe forward link transmission may occupy different frequency bandwidthsso that transmissions on the links do not, or for the most part do not,overlap on any frequency subcarriers. In a TDD system, N forward linkframes and M reverse link frames define the number of sequential forwardlink and reverse link frames that may be continuously transmitted priorto allowing transmission of the opposite type of frame. It should benoted that the number of N and M may be vary within a given superframeor between superframes.

In both FDD and TDD systems each superframe may comprise a superframepreamble. In certain aspects, the superframe preamble includes a pilotchannel that includes pilots that may be used for channel estimation byaccess terminals, a broadcast channel that includes configurationinformation that the access terminal may utilize to demodulate theinformation contained in the forward link frame. Further acquisitioninformation such as timing and other information sufficient for anaccess terminal to communicate on one of the carriers and basic powercontrol or offset information may also be included in the superframepreamble. In other cases, only some of the above and/or otherinformation may be included in this superframe preamble.

As shown in FIGS. 3A and 3B, the superframe preamble is followed by asequence of frames. Each frame may consist of a same or a differentnumber of OFDM symbols, which may constitute a number of subcarriersthat may simultaneously utilized for transmission over some definedperiod. Further, each frame may operate according to a symbol ratehopping mode, where one or more non-contiguous OFDM symbols are assignedto a user on a forward link or reverse link, or a block hopping mode,where users hop within a block of OFDM symbols. The actual blocks orOFDM symbols may or may not hop between frames.

FIG. 4 illustrates the process by which an access terminal 402 probes anaccess network 404 for establishing an access channel 406. The accessterminal 402 sends an access probe 408 to the access network 404 toacquire the access channel 406 and the access network 404 responds withan AccessGrant message 410 to allot the access channel 406 to the accessterminal 402. The procedures and methods required to transmit accessprobe 408 by the access terminal 402 or to receive the access probe 408at access network 404 is controlled by Default Access Channel MACprotocol. Similarly, the messages and procedures for AccessGrant 410sent by the access network 404 are controlled by the Shared SignalingMAC protocol. The communication link between the access network and theaccess terminal may be implemented using communicationprotocols/standards such as World Interoperability for Microwave Access(WiMAX), infrared protocols such as Infrared Data Association (IrDA),short-range wireless protocols/technologies, Bluetooth® technology,ZigBee® protocol, ultra wide band (UWB) protocol, home radio frequency(HomeRF), shared wireless access protocol (SWAP), wideband technologysuch as a wireless Ethernet compatibility alliance (WECA), wirelessfidelity alliance (Wi-Fi Alliance), 802.11 network technology, publicswitched telephone network technology, public heterogeneouscommunications network technology such as the Internet, private wirelesscommunications network, land mobile radio network, code divisionmultiple access (CDMA), wideband code division multiple access (WCDMA),universal mobile telecommunications system (UMTS), advanced mobile phoneservice (AMPS), time division multiple access (TDMA), frequency divisionmultiple access (FDMA), orthogonal frequency division multiple (OFDM),orthogonal frequency division multiple access (OFDMA), orthogonalfrequency division multiple FLASH (OFDM-FLASH), global system for mobilecommunications (GSM), single carrier (IX) radio transmission technology(RTT), evolution data only (EV-DO) technology, general packet radioservice (GPRS), enhanced data GSM environment (EDGE), high speeddownlink data packet access (HSPDA), analog and digital satellitesystems, and any other technologies/protocols that may be used in atleast one of a wireless communications network and a data communicationsnetwork.

FIG. 5A illustrates a flow diagram of process 500, according to anembodiment. The process is invoked by an access terminal for ending anexisting probe transmission, while it is processing an AttemptAccesscommand. This may occur if any of the following events occur. At 502,the access terminal receives an access grant, through SSMACAccessGrantReceived indication on the carrier on which the last probewas transmitted. At 504, the expiration of access grant timer isdetermined. At 506, the protocol receives an Idlestate.IdleHO indicationand at 508, the protocol receives a new AttemptAccess command, whereinthe command is processed after the current probe transmission ends. At510, it is determined if any of the listed events occur and at 514 theprobe transmission is ended, if any of the events occur otherwise at512, the access terminal continues to send the access probe.

FIG. 5B illustrates a processor 550 for establishing an access channel.The processors referred to may be electronic devices and may compriseone or more processors configured for establishing the channel accordingto the embodiment. A processor 552 is configured for receiving an accessgrant, through SSMAC AccessGrantReceived indication on the carrier onwhich the last probe was transmitted. A processor 554 is configured fordetermining the expiration of access grant timer. A processor 556 isconfigured for receiving an Idlestate.IdleHO indication and a processor558 is configured for receiving a new AttemptAccess command, wherein thecommand is processed after the current probe transmission ends. Aprocessor 560 is configured for determining if any of the listed eventsoccur and a processor 564 is configured for ending the probetransmission, if any of the events occur otherwise a processor 562 isconfigured for sending the access probe. The functionality of thediscrete processors 552 to 564 depicted in the figure may be combinedinto a single processor 566. A memory 568 is also coupled to theprocessor 566.

In an embodiment, an apparatus is described which includes means forreceiving an access grant, through SSMAC AccessGrantReceived indicationon the carrier on which the last probe was transmitted, a means fordetermining the expiration of access grant timer, a means for receivingan Idlestate.IdleHO indication and a means for receiving a newAttemptAccess command, wherein the command is processed after thecurrent probe transmission ends. A means is further provided fordetermining if any of the listed events occur and a means is providedfor ending the probe transmission, if any of the events occur otherwisea means is provided for sending the access probe. The means describedherein may comprise one or more processors.

Furthermore, embodiments may be implemented by hardware, software,firmware, middleware, microcode, or any combination thereof. Whenimplemented in software, firmware, middleware or microcode, the programcode or code segments to perform the necessary tasks may be stored in amachine readable medium such as a separate storage(s) not shown. Aprocessor may perform the necessary tasks. A code segment may representa procedure, a function, a subprogram, a program, a routine, asubroutine, a module, a software package, a class, or any combination ofinstructions, data structures, or program statements. A code segment maybe coupled to another code segment or a hardware circuit by passingand/or receiving information, data, arguments, parameters, or memorycontents. Information, arguments, parameters, data, etc. may be passed,forwarded, or transmitted via any suitable means including memorysharing, message passing, token passing, network transmission, etc.

Various modifications to these aspects will be readily apparent to thoseskilled in the art, and the generic principles defined herein may beapplied to other aspects. Thus, the description is not intended to belimited to the aspects shown herein but is to be accorded the widestscope consistent with the principles and novel features disclosedherein.

1. A method of establishing an access channel in a wirelesscommunication system, characterized in that: receiving an AccessGrant ona carrier on which the last probe was transmitted; and ending an accessprobe transmission upon receiving the AccessGrant.
 2. Acomputer-readable medium including instructions stored thereon,characterized in that: a first set of instructions for receiving anAccessGrant on the carrier on which the last probe was transmitted; anda second set of instructions for ending access probe transmission uponreceiving the access grant.
 3. An apparatus operable in wirelesscommunication system, the apparatus characterized in that: means forreceiving an AccessGrant on the carrier on which the last probe wastransmitted; and means for ending access probe transmission uponreceiving the AccessGrant.
 4. A method of establishing an access channelin a wireless communication system, characterized in that: determiningexpiration of an access grant timer; and ending an access probetransmission upon the expiration of the timer.
 5. A computer-readablemedium including instructions stored thereon, characterized in that: afirst set of instructions for determining expiration of an access granttimer; and a second set of instructions for ending access probetransmission upon the expiration of the timer.
 6. An apparatus operablein wireless communication system, the apparatus characterized in that:means for determining expiration of an access grant timer; and means forending access probe transmission upon the expiration of the timer.
 7. Amethod of establishing an access channel in a wireless communicationsystem, characterized in that: receiving an IdleState.IdleHO indication;and ending an access probe transmission upon receiving theIdleState.IdleHO indication.
 8. A computer-readable medium includinginstructions stored thereon, characterized in that: a first set ofinstructions for receiving an IdleState.IdleHO indication; and a secondset of instructions for ending access probe transmission upon receivingthe IdleState.IdleHO indication.
 9. An apparatus operable in wirelesscommunication system, the apparatus characterized in that: means forreceiving an IdleState.IdleHO indication; and means for ending accessprobe transmission upon receiving the IdleState.IdleHO indication.
 10. Amethod of establishing an access channel in a wireless communicationsystem characterized in that: receiving a new AttemptAccess command,wherein the AttemptAccess command is processed after a current probetransmission ends; and ending an access probe transmission on receivingthe new AttemptAccess command.
 11. A computer-readable medium includinginstructions stored thereon, characterized in that: a first set ofinstructions for receiving a new AttemptAccess command, wherein theAttemptAccess command is processed after the current probe transmissionends; and a second set of instructions for ending access probetransmission on receiving the new AttemptAccess command.
 12. Anapparatus operable in wireless communication system, the apparatuscharacterized in that: means for receiving a new AttemptAccess command,wherein the AttemptAccess command is processed after the current probetransmission ends; and means for ending access probe transmission onreceiving the new AttemptAccess command.